1 (-10*(-1 + Sqrt[1 + k^2/(c - I*k0)^2])*(c - I*k0) + 20*(-1 + Sqrt[1 + k^2/(2*c - I*k0)^2])*(2*c - I*k0) - 20*(-1 + Sqrt[1 + k^2/(3*c - I*k0)^2])*(3*c - I*k0) + 10*(-1 + Sqrt[1 + k^2/(4*c - I*k0)^2])*(4*c - I*k0) - 2*(-1 + Sqrt[1 + k^2/(5*c - I*k0)^2])*(5*c - I*k0) + k*Sqrt[Pi]*(Piecewise[{{0, k^2/k0^2 <= 1}}, (2*Sqrt[k^2 - k0^2])/(k*Sqrt[Pi])] + I*Piecewise[{{(2*k0)/(k*Sqrt[Pi]), k0^2/k^2 < 1}, {(2*(k0 - Sqrt[-k^2 + k0^2]))/(k*Sqrt[Pi]), k0^2/k^2 > 1}}, 0]))/(2*k*k0^2)
2 Piecewise[{{SeriesData[k, Infinity, {(-225*c^6)/(2*k0^2) + ((45*I)*c^5)/k0, 0, (-7875*c^6)/4 + (39375*c^8)/(8*k0^2) - ((5250*I)*c^7)/k0 + (525*I)/2*c^5*k0, 0, (-2205*(2025*c^10 - (3310*I)*c^9*k0 - 2250*c^8*k0^2 + (800*I)*c^7*k0^3 + 150*c^6*k0^4 - (12*I)*c^5*k0^5))/(32*k0^2)}, 6, 11, 1], (k0 <= 0 && k^2/k0^2 > 1) || k0 > 0}}, SeriesData[k, Infinity, {-k0^(-2), 0, 1/2, 0, ((5*c*(c - I*k0)^3)/8 - (5*c*(2*c - I*k0)^3)/2 + (15*c*(3*c - I*k0)^3)/4 - (5*c*(4*c - I*k0)^3)/2 + (5*c*(5*c - I*k0)^3)/8 - (5*I)/8*(c - I*k0)^3*k0 + (5*I)/4*(2*c - I*k0)^3*k0 - (5*I)/4*(3*c - I*k0)^3*k0 + (5*I)/8*(4*c - I*k0)^3*k0 - I/8*(5*c - I*k0)^3*k0)/k0^2, 0, ((-5*c*(c - I*k0)^5)/16 + (5*c*(2*c - I*k0)^5)/4 - (15*c*(3*c - I*k0)^5)/8 + (5*c*(4*c - I*k0)^5)/4 - (5*c*(5*c - I*k0)^5)/16 + (5*I)/16*(c - I*k0)^5*k0 - (5*I)/8*(2*c - I*k0)^5*k0 + (5*I)/8*(3*c - I*k0)^5*k0 - (5*I)/16*(4*c - I*k0)^5*k0 + I/16*(5*c - I*k0)^5*k0)/k0^2, 0, ((25*c*(c - I*k0)^7)/128 - (25*c*(2*c - I*k0)^7)/32 + (75*c*(3*c - I*k0)^7)/64 - (25*c*(4*c - I*k0)^7)/32 + (25*c*(5*c - I*k0)^7)/128 - (25*I)/128*(c - I*k0)^7*k0 + (25*I)/64*(2*c - I*k0)^7*k0 - (25*I)/64*(3*c - I*k0)^7*k0 + (25*I)/128*(4*c - I*k0)^7*k0 - (5*I)/128*(5*c - I*k0)^7*k0)/k0^2, 0, ((-35*c*(c - I*k0)^9)/256 + (35*c*(2*c - I*k0)^9)/64 - (105*c*(3*c - I*k0)^9)/128 + (35*c*(4*c - I*k0)^9)/64 - (35*c*(5*c - I*k0)^9)/256 + (35*I)/256*(c - I*k0)^9*k0 - (35*I)/128*(2*c - I*k0)^9*k0 + (35*I)/128*(3*c - I*k0)^9*k0 - (35*I)/256*(4*c - I*k0)^9*k0 + (7*I)/256*(5*c - I*k0)^9*k0)/k0^2}, 0, 11, 1]]